Amazon 128gb microSDXC UHS-I New Version 80MB/s 533x really slow

So I bought this card off Amazon and its slower than a old 64gb card I had. It is supposed to be the new version.

Amazon Card

SD Insite says its a SL128 rev8.0 Manufactured Aug 2015. SD Physical Layer 3.0 SDXC Card Security version 3.xx

Using my PC I only seen up to 20mb reads and 9 to 12 writes.

Using A1 SD Bench memory card test I see 20mb reads and 9.66 writes on the long test. Not what Amazon said. Is the a legit card or bait and switch or just plain false advertising.

On the back off the envelope it says SDSQUNC-128G-GN6MA


There are a few factors that may be causing the slower speeds. 

  1. this is a UHS card. To get the Full speed you will need a UHS compatible reader

  2. To get the full speed you will need a USB 3.0 reader and a USB 3.0 port. Do you have a UHS enabled USB 3 reader? If so what is the type of reader?

  3. The advertised speed of 80MB/s is for reads. Write speed is not specified. Write speed could be as low as 10MB/s. 

I know writes are slower but reads are 20mb on PC with a USB3.0 card reader and Samsung note 10.1 2014.

The reader on the PC is one I bought from Newegg and installed in a front slot in the computer. Not sure what brand etc. IT plugs into a USB 3.0 port on my Asus motherboard.